Advertisement

Folia Microbiologica

, Volume 42, Issue 4, pp 390–394 | Cite as

Mutational changes in the hemagglutinin of equine H3 influenza viruses result in the introduction of a glycosylation site which enhances the infectivity of the viruses

  • C. A. O. Adeyefa
  • J. W. McCauley
  • O. Tomori
Papers

Abstract

The complete amino acid sequences of the hemagglutinin (HA) glycoprotein of three equine-2 influenza viruses from tropical Africa are presented in comparison with that of a well characterized European equine-2 virus (Suffolk/89) and a consensus sequence from the database. The sequences of the tropical African viruses were deduced from the complete nucleotide sequences of their HA genes reported earlier. Mutational changes in the nucleotide sequences resulted in amino acid changes in the HA which led to the introduction of a new asparagine-linked (N-linked) glycosylation site in two viruses. This new glycosylation site enhanced the infectivity of these viruses as investigated by plaque assay, virus titration in embryonated chicken eggs and tunicamycin treatment. The role of N-linked glycosylation of influenza virus HA glycoprotein in virus infectivity, antigenicity and immunogenicity is discussed in the light of the results of our previous and present investigations.

Keywords

Influenza Influenza Virus Glycosylation Site Avian Influenza Virus Plaque Assay 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Adeyefa C.A.O., McCauley J.W.: Outbreak of equine influenza in polo horses in Ibadan, Nigeria: virus isolation, clinical manifestation and diagnosis.Vet. Res. 134, 683–684 (1994).Google Scholar
  2. Adeyefa C.A.O. McCauley J.W.: Antigenic variation among Nigerian strains of equine H3 HA influenza viruses.J. Sci. Res., in press (1996).Google Scholar
  3. Adeyefa C.A.O., Quayle K., McCauley J.W.: A rapid method for the analysis of influenza virus genes: application to the reassortment of equine influenza virus genes.Virus Res. 32, 392–398 (1994).CrossRefGoogle Scholar
  4. Adeyefa C.A.O., McCauley J.W., Daneji A.I., Kalejaiye O.A., Bakare A., Ashimolowo A.:In-vitro andin-vivo studies on the immunogenicity of influenza A viruses in equines.Trop. Vet. 13, 153–168 (1995).Google Scholar
  5. Adeyefa C.A.O., Hamblin C., Cullinane A., McCauley J.W.: Nationwide serological survey of equine influenza in Nigeria.Revue Elev Med. Vet. Pays. Trop. 49, 2–5 (1996a).Google Scholar
  6. Adeyefa C.A.O., James M.L., McCauley J.W.: Genetic and antigenic analysis of equine influenza viruses from tropical Africa in 1991.Epidem. Infect. 117, 367–374 (1996b).Google Scholar
  7. Bosch F.X., Garten W., Klenk H.D., Rott R.: Proteolytic cleavage of influenza virus hæmagglutinin: primary structure of the connecting peptide between HA1 and HA2 determines proteolytic cleavability and pathogenicity of avian influenza viruses.Virology 118, 725–735 (1981).CrossRefGoogle Scholar
  8. Caton A.J., Brownlee G.G., Yewdell J.W., Gerhard W.: The antigenic structure of influenza virus A/PR/8/34 hæmagglutinin (H1 subtype).Cell 3, 417–427 (1982).CrossRefGoogle Scholar
  9. Clague M., Schoh C., Blumenthal R.: Delay time for influenza virus hæmagglutinin-induced membrane fusion depends on hæmagglutinin surface density.J. Virol. 65, 2402–2407 (1991).PubMedGoogle Scholar
  10. Gibson C.A., Daniels R.S., Oxford J.S., McCauley J.W.: Sequence analysis of the equine H7 influenza virus hæmagglutinin gene.Virus Res. 22, 93–106 (1992).PubMedCrossRefGoogle Scholar
  11. Hu A., Cattaneo R., Schwartz S., Norrby E.: Role of N-linked oligosaccharide chains in the processing and antigenicity of measles virus hæmagglutinin protein.J. Gen. Virol. 74, 1043–1052 (1994).CrossRefGoogle Scholar
  12. Knipe D.M.: Virus-host-cell interactions, inVirology, 2nd ed. (B.N. Fields, D.M. Knipe, (Eds). Raven Press, New York 1990.Google Scholar
  13. Skehel J.J., Stevend D.J., Daniels R.S., Douglas A.R., Knossow M., Wiley D.C.: A carbohydrate side chain of hæmagglutinin of Hong Kong influenza viruses inhibits recognition by a monoclonal antibody.Proc. Nat. Acad. Sci. USA 81, 1779–1783 (1984).PubMedCrossRefGoogle Scholar
  14. Wiley D.C., Skehel J.J.: The structure and function of the hæmagglutinin membrane glycoprotein of influenza virus.Ann. Rev. Biochem. 56, 365–394 (1987).PubMedCrossRefGoogle Scholar
  15. Wood J., Mumford J.: Epidemiology of equine influenza.Vet. Res. 130, 126 (1992).Google Scholar

Copyright information

© Folia Microbiologica 1997

Authors and Affiliations

  • C. A. O. Adeyefa
    • 1
    • 2
  • J. W. McCauley
    • 1
  • O. Tomori
    • 3
  1. 1.Pirbright Laboratory, PirbrightInstitute for Animal HealthSurreyUK
  2. 2.Department of Veterinary MedicineUniversity of IbadanIbadanNigeria
  3. 3.Department of VirologyUniversity of IbadanIbadanNigeria

Personalised recommendations